When your chainsaw is not cutting straight it can be very frustrating.
If you cut firewood to heat your home, or simply enjoy creating a stockpile of wood for evening campfires, having a chainsaw that cuts crooked is not an uncommon problem.
These half moon cuts make it virtually impossible to process firewood, so it's important to understand why your saw is cutting like this, and more importantly, how to fix it.
There's generally two parts of your chainsaw that will cause a crooked cut, the chain or the bar.
The most common problem for a crooked cut is a dull or damaged chain.
As you use your chainsaw, it will gradually become dull over time and a good rule of thumb is to "touch up" or hand sharpen your chain a few strokes on every fill up of gas.
This maintenance can help prevent a lot of problems as you use your saw.
Typically, as you're cutting through a log you'll hit a rock that causes one side of your chain to become dull.
This is the most common reason why your chainsaw is not cutting straight.
When you hit the rock, one side of the chain may stay sharp while the other becomes instantly dull.
The sharp side of the chain will continue to cut into the wood and pull the bar into that direction, creating the crooked cut.
It's similar to paddling a canoe or kayak.
If you paddle or dig in on one side harder than the other, your canoe or kayak will turn that direction, just like the teeth of your chainsaw chain dig in and pull the bar.
Also, just a few dull or damaged teeth on one side of the chain can cause this problem.
It doesn't necessarily have to be every tooth.
A lot of times when your chain is damaged to the point it's creating uneven cuts, it's easier to remove the chain and either take it to a shop to have it professionally sharpened, or if you have an electric bench grinder you can repair the chain yourself.
The bench grinder works great in these situations because you can take a consistent amount of material off each tooth at the correct angle.
This can sometimes be difficult with a hand file, because a hand file tends to work better for keeping a chainsaw chain sharp as opposed to repairing a damaged chain.
When sharpening your chain it's important to keep each side of the teeth as even as possible.
Although keeping the tooth length on each side of the chain is important, it's the angle that really counts.
A lot of people tend to sharpen a chain with a slightly different angle or pressure depending on whether you're right of left handed.
When you switch to the other side of the chain, you'll need to make sure your angle is consistent with the other side to make sure you get an even cut.
If you look closely at the top of the tooth you'll see a line that indicates the proper angle to hold your file at when you sharpen the tooth.
Also, when you run the file through the tooth, make sure you apply some slight upward pressure to the file to make sure you sharpen the top cutting edge of the tooth.
If you just sharpen the gullet, the chain won't cut very well.
You need to sharpen the gullet along with the top cutting edge which creates a nice sharp corner on the chain.
Basically, if the teeth of your chain are sharp and they're sharpened at the correct angle, your chainsaw will cut straight.
Another reason why your chainsaw is not cutting straight could be due to a damaged or worn bar.
A worn bar is typically caused by a dull chain because it causes you to force the bar through the wood as opposed to the chain pulling itself as it cuts.
As you push on the bar, it causes the bar to flare out on the sides.
The most common area where the bar rails will wear is right in front of the powerhead because that's where most of the cutting takes place.
There's a few simple steps you can take to improve the longevity of your bar.
First, if you feel the edge of your bar start to flare you can lay it down on a flat surface (after you remove the bar and chain from the saw), take a flat file and knock down the burr near the bar rail.
It doesn't take much filing, and once one side is done you can flip it over and do the other side.
Also, take the edge of a credit card, small screwdriver or specially designated tool and clean out the wood and oil debris from inside the grove of the bar while you have it off.
This is also a great time to lubricate the sprocket tip on the bar too.
Finally, when re-installing the bar, flip it over.
Flipping the bar occasionally will promote even wear on the bar and reduce the chances of your chainsaw cutting crooked.
The most common cause of smoke coming from your bar or chain while you cut is a dull chain or a lack of bar and chain oil.
Like we mentioned earlier, when your chain is dull it causes you to apply more downward force to your cuts.
This downward pressure tries to force the chain through the wood creating smoke, instead of the chain cutting through the wood on its own.
You should also check to make sure your saw is full of bar oil.
Chainsaw bar oil prevents wear on the bar and reduces friction, which allows the chain to travel smoothly across the bar.
Also, check to make sure the bar oiler hole on the chainsaw bar is not obstructed with sawdust which can sometimes cause the oil to not flow onto the bar.
If your chainsaw is not cutting straight, chances are your chain is dull on one side.
Even the smallest amount of sand or dirt on the edge of a log can dull a sharp chain.
Once you feel like your saw is starting to loose its ability to pull itself through the log it's time to touch up the chain with a hand file.
Although you might not notice your saw cutting crooked on smaller pieces of wood, large rounds will make it become very apparent.
As long as you keep your chain sharp and take the time to occasionally flip your bar over, you can eliminate those annoying angled cuts that make cutting firewood difficult and unsafe.